Calculators
Compare capital gains tax on an investment property under the existing 50% discount and the post-July 2027 rules of inflation indexation plus a 30% minimum tax.
Simplified model, illustrative only.
An investment property sold before reform commencement stays under the existing 50% discount framework.
Example taxable gain after the 50% discount
$117,500
This is a simplified example of the taxable amount, not a full tax return result.
Total cost base
$685,000
Nominal gain
$235,000
Taxable gain after the 50% discount
$117,500
How the taxable gain is worked out
max(0, $235,000 × 50.0%)
The whole gain is halved, whether it came from real growth or from inflation.
Existing model. For assets sold before 1 July 2027, the examples keep the existing 50% CGT discount treatment for eligible holdings.
Post-reform model (from 1 July 2027). For later gains, the examples show nominal gain reduced by CPI indexation of the cost base and then apply the 30% minimum tax floor.
Existing asset sale (pre-July 2027). An investment property sold before reform commencement stays under the existing 50% discount framework.
Asset held across the reform date. A property bought before 1 July 2027 and sold on or after it is split into pre-reform and post-reform value movement.
New investment (post-July 2027). A rental property acquired after reform commencement cannot use the 50% discount; its cost base is indexed to CPI instead.
New residential housing carve-out. Eligible new builds can be compared under both the legacy 50% discount example and the post-reform indexation model.
No real gain after inflation. If inflation absorbs the post-reform nominal gain, the indexed gain is floored at zero in this example.
Held for 12 months or less. Both the 50% CGT discount and cost base indexation need the sale to happen more than twelve months after acquisition, so a quick resale keeps the full nominal gain taxable.
Capital loss or zero gain. If sale proceeds do not exceed the relevant cost base, the tool shows no taxable gain and highlights the loss or nil outcome.
Ineligible or out-of-scope property. Trust structures, joint ownership, foreign residency issues, and non-eligible housing are outside this simplified tool.
Assumption-heavy valuations. The cross-reform example depends on an assumed market value at 1 July 2027, which can materially change the split outcome.
The Treasury Laws Amendment (Tax Reform No. 1) Act 2026 received Royal Assent on 26 June 2026. For CGT events from 1 July 2027 it removes the 50% CGT discount for Australian resident individuals and trusts, indexes the cost base to CPI instead so only the real (above-inflation) gain is taxed, and adds a 30% minimum tax on those gains. This page compares the old and new treatment using the numbers you enter.
The new rules apply to CGT events on or after 1 July 2027. Assets bought and sold before that date keep the 50% discount. An asset bought before 1 July 2027 and sold later is treated as sold and reacquired on that date: the gain up to 1 July 2027 keeps the 50% discount and the gain after it is indexed. The Act uses the market value at 1 July 2027 for that split, or a prescribed apportioning method if you choose one.
The 50% discount simply halves your nominal capital gain before tax, regardless of how much of that gain is real growth versus inflation. The indexation method instead raises the cost base in line with CPI, so only the real (above-inflation) gain is taxed. When inflation is high relative to the gain, indexation can leave little or no taxable gain; when inflation is low, the older 50% discount is often more generous.
No. Both the 50% CGT discount and cost base indexation need the CGT event to happen more than 12 months after you acquire the asset, so selling within the first year leaves the whole nominal gain taxable. This calculator applies that rule automatically: enter a purchase and sale date twelve months apart or less and both are switched off. Buying and selling on the same day of the year does not qualify either.
The Act indexes each cost base amount by the ratio of the CPI index number for the quarter of sale to the CPI index number for the quarter the amount was spent. This tool simplifies that to one cumulative inflation figure you enter for the whole holding period. It multiplies that percentage by the relevant cost base (the total cost base for a property bought after the reform, or the estimated 1 July 2027 value for a property held across the reform date) and subtracts the result from the nominal gain, floored at zero.
It is a floor, not a flat rate. If the income tax your capital gain adds at your marginal rate is less than 30% of the gain, you pay extra tax to make up the difference; if your marginal rate is already 30% or more, nothing extra is due. People receiving certain income support payments during the year, such as the Age Pension, JobSeeker or Family Tax Benefit, are exempt. The figure shown here is 30% of the indexed gain, which is the least tax the gain can attract.
Yes. For an eligible new residential dwelling you can keep the 50% discount (and the minimum tax does not apply) or choose indexation plus the minimum tax instead. The tool shows both side by side once you confirm the property is an eligible new build. Which properties qualify is set by a ministerial legislative instrument that had not been made as of September 2026, so check eligibility with your accountant.
If the sale proceeds do not exceed the relevant cost base, the calculator reports a capital loss and shows no taxable gain rather than a negative figure. Real capital loss treatment is more involved: losses are generally offset against other capital gains in the same year, and any unused amount is carried forward. This tool looks at one property in isolation, so it cannot show that interaction.
No. This page is for self-study and education only. The scenarios use simplified assumptions and the values you enter, and they ignore many real-world factors such as trust or joint ownership, foreign residency, capital losses from other assets, main residence exemptions, and your marginal tax rate. Consult a registered tax agent or accountant for your own situation.
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Taxable gain after the 50% discount
$117,500.00